Today, containers are used for transporting load goods everywhere in the entire world. When containers should be conveyed to other continents, this preferably takes place by the containers being loaded on vessels for further transportation to the place of destination. In order for the transportation via vessel should work in safe way, it is required among other things that all containers on board have to be transportation-locked by means of some type of locking device. Today, four container locks are placed in each corner/bottom of a container. Each lock then locks into either a subjacent container alternatively the vessel deck (if the container is farthest down in a pile). Today, up to seven (7) containers are piled on each other in transportation via vessel.
There exists today a number of different types of locks on the freight market. Certain types of container locks comprise an automatic, mechanical locking procedure. A problem in this connection is that a visual inspection has to take place manually to guarantee that the locks have locked in intended manner. However, to unlock a container lock using today's solutions still has to take place manually. This operation takes place by staff walking around with long rods to reach up to locks on different levels, alternatively is hoisted up by means of a particular crane cab to unlock the locks by hand.
A problem of using wirelessly controlled container locks to decrease the manual work is that it is not desired to unlock all locks that are within radio range, but only those locking the container or containers to be lifted. It means that the system somehow has to possess knowledge about which container locks that are present on the respective container. See, e.g., WO2006/025790 A1, which shows remote-controlled container corner locks, where each lock that in connection with the lock being connected to a certain container is programmed with a number specific for the same container. These numbers are then stored in a database. Thereby, remote control is enabled of the locking and unlocking function by sending commands to locks that possess these preprogrammed numbers. However, to be able to remote control the locks, knowledge is required about these preprogrammed numbers.
By SE 527 608 C2, an additional method for remote control of container locks is previously known. In connection with locking, an automatic group allocation takes place, where the four locks locking a specific container are allocated a unique group identification number. Remote controlled unlocking of the locks then takes place by an external unit sending out a request regarding which locks that are in the vicinity. Each lock sensing the request sends out its group identification number as answer, all answers being processed and it being established which locks are locking the container in question. Even if this method works well, it is desirable to additionally improve it and provide a way to determine the relative position of each container corner lock and/or groups of container corner locks.